Lamp switch



Jan. 10, 1956 H. c. DUETZMANN 2,730,586

LAMP SWITCH Filed Sept. 1, 1953 INVENTOR HANS C. DU ET ZMAN N HIS ATTORN EYS United States Patent LAMP SWITCH This invention relates to a switch, and more particularly to an improved and simplified switch for controlling the energization of a portable electric lamp.

Flashlights and other types of portable lamps require switches to control the energization of their lamp bulbs. Many types of portable lamps employ sheet metal cases in which the lamp is carried, and it is desirable that a dependable lamp circuit switch be provided on the casing wall for operation from the outside thereof.

It is the object of the present invention to provide a simple and dependable switch construction for mounting on the wall of a lamp case, and more particularly to provide a switch of this nature that carries its contact making and breaking parts within the casing. More particularly, the switch of the present invention comprises a single movable operating member formed of insulating material having a part that extends through an elongated opening or slot in a casing wall and cooperates with resilient conductive contact means Within the casing to make and break an electric circuit. The switch is preferably so constructed that the resilient contact means also releasably holds the movable member in its circuit opening and closing positions.

In describing the invention in detail, reference will be made to the accompanying drawing, in which an embodiment thereof is illustrated.

In the drawing:

Fig. 1 is a sectional elevation of a lamp with a switch embodying the invention;

Fig. 2 is an enlarged perspective view of the switch structure;

Fig. 3 is a sectional view of the switch mechanism with the switch in the open position;

Fig. 4 is a sectional view similar to Fig. 3, with the switch in its closed position; and

Fig. 5 is a perspective view showing a modified form of spring contact finger for the switch.

In Fig. 1 there is shown a portable lamp of the type that may be secured to the forehead of the user by a head band. The switch of the invention may be used with various forms of lamps and that shown is merely one of many with which the switch may be employed.

The lamp shown comprises a sheet metal casing having a wall 6 provided with a support 7 and carrying a reflector 8 secured in a circular casing opening by a screw ring 9 which also holds a lens 10 over the reflector. A lamp bulb 11 is carried in a socket 12 mounted at the apex of the reflector 8, and electrical energy is supplied to the bulb through a circuit including a wire 13 suitably connected to the central contact of the socket 12 and a wire 14 connectible to the casing wall 6 through the switch of the invention, as hereinafter described. The wires 13 and 14 enter the casing through a suitable opening 30 in the casing wall 6 and are connected to a battery or other source of electrical energy, not shown.

The casing wall 6 is provided with an elongated opening or slot 15, here shown as rectangular in form. In

casing equipped this slot, there is mounted for sliding movement from end to end thereof a movable operating member, generally designated M, and preferably formed of substantially rigid insulating material, such as polystyrene, hard rubber or some other suitable plastic.

As best shown in Fig. 2, the operating member M comprises an outer head or part 16 which overlies the slot 15 and the adjacent surface of the casing wall 6 and an inner or contact carrying part 17 which extends into the interior of the casing through the slot 15.

Various means may be provided to slidably mount the operating member M in such a manner that its inner part 17 may move from end to end of the slot 15. As shown, the opposite sides of the inner part 17 are provided with grooves 18 that extend parallel to the casing wall and the long edges of the slot 15 and lie immediately within the casing, and the inner edges of the parallel legs 19 of a bifurcated plate 20 engage these grooves and so slidably support the operating member. The plate 20 lies against the inner surface of the casing wall 6 and may be secured thereto by a rivet 21.

Also secured to the casing wall by the rivet 21 is a spring contact finger 22, the free end of which extends over the slot 15 and resiliently bears against the inner face of the inner part 17 of the operating member M. A tang 31 may be struck up from the plate 20 to overlie the base of the spring finger 22 in order to provide a rigid anchor, as shown in Fig. 2. The free end of the spring finger 22 is preferably formed by bending to present a rounded surface 24 for engagement with the inner face of the part 17.

The inner contact carrying part 17 is provided with a central recess 25 within which is secured a contact member in the form of a metal screw 26, beneath the head of which the bare end of the wire 14 is clamped. The walls of the recess 25 are provided with transversely aligned notches 27 that extend below the level of the head of the screw 26. The end corner of the inner part 17 nearest the end of the slot 15 at which the spring finger 22 is mounted is preferably bevelled, as shown at 28.

When the operating member M is moved to a position where the rounded end 24 of the spring finger drops into the notches 27, electrical contact is made between the spring finger and the head of the screw 26. This is the closed position of the switch shown in Fig. 4, and the contacts so made connect the wire 14 to the casing wall 6 and complete the energizing circuit for the lamp bulb 11. In this closed position, the operating member M is held by the resilient engagement of the finger end 24 with the notches 27 in a position in which its inner part 17 abuts one end of the slot 15. To open the switch, the operating member is moved along the slot 15 by manual force applied to its head part 16 to the position shown in Figs. 2 and 3. During this movement, the rounded end of the 1" spring finger 22 is lifted out of the notches 27 and springs down against the bevelled corner 28 of the inner part 17, thereby holding the operating member in the open position.

If desired, the spring finger may be formed integral with the plate that slidably mounts the operating member in the casing slot. Such a construction is illustrated in Fig. 5, wherein the plate 20 has spaced legs 19' for slidably supporting the operating member, and the spring finger 22 is struck up from the plate, as shown.

I claim:

1. A switch comprising a wall member having an elongated opening therein, a movable operating member of insulating material having a head adjacent the wall member and a contact carrying part extending through said opening, means securing said operating member for sliding movement in said opening, a conductive contact secured to said contact carrying part and a conductive spring finger overlying said opening and engaging said contact carrying part for selective engagement and disengagement with said contact upon sliding movement of said member along said opening.

2. A switch comprising a conductive casing Wall having an elongated slot therein, an operating member of insulating material comprising an outer head part disposed on one side of said wall and an inner element extending through said slot, means mounting said operating member for sliding movement lengthwise of said slot between the opposite ends of said slot, a conductive contact secured to said inner element and a spring contact finge' secured to said casing wall and resiliently engaging said conductive contact in the path of movement of said contact.

3. A switch comprising a conductive casing wall having an elongated slot therein, an operating member of insulating material comprising an outer head part disposed on one side of said wall and an inner element extending through said slot, means mounting said operating memher for sliding movement lengthwise of said slot, said inner eiement having a recess in the inner face thereof, a conductive contact secured in said inner element recess, and a. spring contact finger secured to said casing wall and having a free end overlying said slot and resiliently engaging the inner face of said inner element in the path of movement of said contact whereby said spring finger engages and disengages said contact when said operating member is moved in said slot.

i. A switch comprising a conductive casing wall having an elongated slot therein, an operating member of insulating material comprising an outer head part disposed on one side of said wall and an inner element extending through said slot, said inner element having grooves in opposite sides thereof extending lengthwise of said slot, a bifurcated plate secured to said casing wall adjacent said slot and having parallel legs engaging said inner element, grooves to support said operating member for sliding movement lengthwise of said slot, a conductive contact secured to said inner element and a spring contact finger secured to said casing wall and resiliently engaging said conductive contact in the path of movement of said contact.

5. A switch comprising a conductive casing wall having an elongated slot therein, an operating member of insulating material comprising an outer head part disposed on one side of said wall and an inner element extending through said slot, said inner element having grooves in opposite sides thereof extending lengthwise of said slot, a piate secured to said casing wall adjacent said slot and having parallel legs extending adjacent opposite sides of said slot and engaging said inner element grooves to support said operating member for sliding movement lengthwise of said slot, a spring finger struck from said plate and having a free end overlying said slot and resiliently engaging the inner end of said inner element, and a conductive contact secured to the inner end of said inner element for engagement and disengagement with said spring finger upon sliding movement of said operating member to diiferent position along said slot.

References Cited in the file of this patent UNITED STATES PATENTS I N-l 

